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Development and Research of Three-phase
Multizone AC-DC Converters
Alexander G. Volkov, Gennady S. Zinoviev, IEEE Member
NSTU, Novosibirsk, Russia
Abstract – In the given work has been done comparative
analysis of work of new three-phase schemes AC-DC converters: a three-zone bridge scheme, a two-zone bridge
scheme, two-zone null scheme, and also the two-zone
scheme used one-phase bridges. It is shown that in new
schemes of rectifiers of three-phase voltage inverse voltage
on gates essentially decrease and substantially power indicators, in comparison with the schemes used at present are
improved. Total harmonic distortion of direct voltage, an
input current, and also the power factor, received computer modeling in PSIM are presented.
Keywords – multizone, rectifier, total harmonic distortion,
power factor.
I.
INTRODUCTION
THE PRESENT TIME for electric mine hoist maATchines
are widely used 6 - and 12-pulse schemes
with irreversible thyristor converters in the armature
circuit and reversible converters in the grid excitation.
Parent sample of this drive was developed in CDB
"Electric drive" in 1975 and introduced in 1977 on skip
elevating of the first Berezniki potash plant [1, 2].
With a lower speed in comparison with the scheme with
reversible thyristor converter in the armature circuit
when developing managing and disturbing effects, these
schemes, however, satisfies the technology requirements for mine winders for the following reasons:
• The mine hoist installations and normal modes are no
rapid changes in load torque;
• The mine hoist installations presence of elastic bonds
in the form of rope to exclude the possibility of rapid
changes of control actions is required;
However, hardware circuits with irreversible thyristors
converters in the armature circuit and the analog control
system and the regulation of costs significantly less
hardware circuits with reversing thyristor converters.
In this paper a fundamentally new scheme of rectification, which allow not only significantly reduce the reverse voltage across the valves, but also improve the
quality of output voltage and input power factor rectifier
surface are proposed. Improving the quality of output
voltage leads to a decrease in the cost of the rectifier
output filter, and improving the quality of the input current of rectifier leads to improved electromagnetic compatibility of converter with the supply grid, especially in
cases of comparable power rectifier and power supply.
In this case, the load is an electric drive up to 600 kW.
This reduces the cost of additional equipment (passive
and active filters, reactive power compensators), designed to reduce the reaction of the rectifier on the supply grid.
The second area of application of these high-voltage
rectifying schemes is the use of it as the first block to
supply regulated DC bus for the second block energy
conversion to alternating current, which may be a voltage inverter or inverter current [3].
II. STATEMENT OF THE PROBLEM AND
INVESTIGATED SCHEMES
In this section, are compared the new three-phase highvoltage rectifiers, energy characteristics, as well as the
number of semiconductor elements in the scheme. It is
shown that the new schemes of three-phase multizone
(n-zone generally) significantly reduced the number of
rectifier thyristors, and reduces the reverse voltage on
gates.
Figures of total harmonic distortion of output voltage
input current and input power factor, obtained by computer modeling in PSIM are shown. At Fig.II.1 (a, b) are
3-zone and 2-zone bridge schemes, respectively, and
Fig. II.2 (a, b) the schemes of the 3-zone zero and 2zone scheme for the rectification used single-phase
bridges, respectively.
As the investigated schemes three-phase schemes of
rectifying: the three-zone bridge, a two-zone bridge, a
two-zone null scheme, as well as a two-zone scheme on
single-phase bridge were used (Fig.II.1 and Fig.II.2).
Supply of rectifier implemented on a partitioned secondary winding of three-phase transformer.
The scheme in Fig. II.2 by parallel connection of three
schemes of one-phase rectifiers is received [4, 5].
As shown in Fig. III.3. the best measure the power factor is achieved by using a three-phase three-zone
schemes of rectification.
B. Total harmonic distortion of input current
а)
б)
Fig. II.1. Investigated schemes of rectifiers: a) the bridge three-zone
scheme of rectifying b) ) the bridge two-zone scheme of rectifying
The quality of the input current estimated rate of its total
harmonic distortion. Figures depending on the degree of
voltage regulation, investigation schemes shown in Fig.
III.4.
а)
b)
Fig. II.2. Investigated schemes of rectifiers: a) the three-zonal null
scheme of rectifying b) two-zone scheme used single-phase bridges
Additional diodes in each bridge provide a fixing of
voltage on the thyristors at appropriate levels of voltage
transformer section.
III. EXPERIMENT
Fig. III.4. Harmonic distortion of input current for the investigated
schemes of recrifying
In Fig. III.5 below shows the voltage waveforms of a
single phase supply grid, as well as the input current
drawn by the converter.
This section contains figures illustrating the results
of computer modeling for the investigated schemes,
specifically: Input power factor, Total harmonic distortion of output voltage, total harmonic distortion of input
current.
A. Power factor
The quality of the input energy rated by input power
factor as function of the degree of regulation of direct
voltage, as shown in Fig. III. 3.
a)
b)
Fig. III.3 Input power factor as degree of regulation of the direct voltage.
c)
a)
d)
b)
Fig. III.5. Oscillograms of the input current and voltage for schemes a)
the three-zone bridge, b) a two-zone bridge, c) the three-zone null, d)
a two-zone used single-phase bridges
C. Total harmonic distortion of output voltage
The quality of the output voltage and current rated by
their total harmonic distortion. Figures depending on the
degree of voltage regulation in the second zone of regulation are shown in Fig.III.6.
c)
d)
Fig. III.7. Oscillograms of output voltage and current for the schemes
a) the three-zone bridge, b) a two-zone bridge, c) the three-zone null,
d) a two-zone used single-phase bridges
Fig. III.6. Total harmonic distortion of output voltage depending on
the degree of voltage regulation.
Fig. III.7. shows the output, the direct voltage and direct
current in steady state.
Multizone direct voltage control reduces the reverse and
forward voltage on the thyristors, which in this case do
not exceed the voltage of one section of the secondary
winding of the transformer.
The research results are presented in Tab. I:
Тable I
DC to AC, due to reduced reverse voltage across the
controlled rectifier, the improved quality of output voltage, better input current and, consequently, better electromagnetic compatibility and energy efficiency.
REFERENCES
[1] Kolev St. Н, Kalchev A.K., ”External the characteristic and operating modes 12-pulse converter with the reduced losses.” / Ref. Magazine «The Electrical engineer and electric power industry» 21, № 9,
1977, 117 – 120.
[2] Evdokimov S. A, Shchurov Н. I. “The generalized 12n-phase
rectifier”. The electrical engineer, 2010. №12.
[3] Bin Wu and Frank A. DeWinter, “Voltage Stress on Induction
Motors in Medium Voltage (2300–6900-V) PWM GTO CSI Drives”,
ieee transactions on power electronics, vol.12, no.2,
[4] Zinovev G. S., “The alternating voltage converter in the constant”
The patent of the Russian Federation № 2368998, the Bulletin № 27,
2009.
[5] Volkov A.G., Zinovev G. S, Kosarev A.P. «Development and
research of multizone converters”, Conference in micro/nano tehnology and electronic devices», Novosibirsk State Technical University,
2009. Altai, Erlagol - p: 372-378
[6] Datskovskij L.H., Rogovoy V.I, Kuznetsov I.S. «The electric drive
of mine hoist engines», "Electrical engineer" №1/2010 year.
The table shows that the use of two-zone schemes of
rectification provides a good quality voltage, practically
does not differ from the voltage in a three-zone scheme,
as well as a significant decrease in the number of semiconductor controlled gates. Number of diodes is also
reduced by 25%. In the case when getting a good voltage quality is a secondary task, possibly using the threezone null scheme that differs significantly from the
bridge schemes in number of semiconductor devices.
Alexander G. Volkov – Master of Engineering and Technology of
faculty REF NSTU, the engineer of
industrial electronics department.
IV. CONCLUSION
Gennady S. Zinoviev – the student, the post-graduate student, the
From these results it is clear, that the quality of
input and output of investigated converters located at
the same level. However, the reverse voltage on gates
significantly reduced, accordingly, the number of
controlled gates in the classical high-voltage rectifiers,
when you need a serial connection of thyristors in them.
As a result, the total number of thyristors in the
proposed scheme will be no less than two times less
than in the existing scheme of the rectifier, if we use
same type thyristors, whose parameters are determined
by the voltage (usually with a double margin) a
secondary winding of the transformer. Applications for
these powerful multizone rectifiers can be especially
powerful DC electric drive. Unfortunately today this
type of electric drive is displaced by AC drive. In this
field investigated schemes can be used as a first block of
electrical energy from AC to DC for subsequent supply
the DC bus and the second block of power conversion
senior lecturer, doctoral candidate of
NSTU, the professor of industrial electronics department of NSTU, the research
supervisor SRL OCS (Optimization of
energy in converting systems). The author of the textbook on the power electronics, two pornographies of electromagnetic compatibility
gated converters, 70
patents
and
more
than 200 publications.